ABCMdb

PMID: 18467194

Frentescu L, Brownsell E, Hinks J, Malone G, Shaw H, Budisan L, Bulman M, Schwarz M, Pop L, Filip M, Tomescu E, Mosescu S, Popa I, Benga G
The study of cystic fibrosis transmembrane conductance regulator gene mutations in a group of patients from Romania.
J Cyst Fibros. 2008 Sep;7(5):423-8. Epub 2008 May 7., [PubMed]

Sentences

No. Mutations Sentence Comment

5 ABCC7 p.Trp1282* ABCC7 p.Gly542* Other frequent mutations noted are: G542X (3.9%), W1282X (2.3%), and CFTRdele2,3(21 kb)(1.6%); the remaining mutations have frequencies below 1%. Login to comment 35 ABCC7 p.Arg117His ABCC7 p.Trp1282* ABCC7 p.Arg553* ABCC7 p.Arg334Trp ABCC7 p.Arg347Pro ABCC7 p.Asn1303Lys ABCC7 p.Gly542* Nine patients were tested for 13 mutations [F508del, 1677delTA, I507del, R117H, R553X, 621+ 1GNT, R334W, R347P, G55D, G542X, W1282X, N1303K, CFTR dele2,3(21 kb)] in the Department of Human Genomics, Institute for Molecular Biology and Genetics, National Academy of Science, Kiev, Ukraine (Table 1). Login to comment 39 ABCC7 p.Trp1282* ABCC7 p.Asn1303Lys ABCC7 p.Gly542* The following 117 samples were analyzed in DCMB, for a variable number of common mutations between 3 and 26, starting with F508del, I507del and 1677delTA, and continuing with the commercial kits CF-3 (G542X, W1282X and N1303K), CF-8 [F508del, I507del, 1677delTA, CFTRdele2,3 (21 kb), 2143delT, 2184insA, 394delTT, 3821delT], both produced by the Research Center for Medical Genetics, Moscow, Russia, and Elucigene CF20. Login to comment 47 ABCC7 p.Gly551Asp ABCC7 p.Arg117His ABCC7 p.Trp1282* ABCC7 p.Arg553* ABCC7 p.Arg334Trp ABCC7 p.Arg347Pro ABCC7 p.Asn1303Lys ABCC7 p.Gly542* ABCC7 p.Gly542* ABCC7 p.Trp1282Arg ABCC7 p.Asn1303Arg ABCC7 p.Asn1303Phe For other Table 1 PCR primers and references for the analysis of 13 common mutations in the CFTR gene Mutation Name of primers Restriction enzyme Reference R334W 7F MspI [10] R347P 7R Hin6I R117H 4A Hin6I [11] 621+1GNT 4B HincII N1303K N1303F DdeI [12] N1303R W1282X W1182F MnlI [13] W1282R [14] G551D 11i5 HincII [15] R553X 11i3 Sau3A G542X 11ex3` MvaI [11] G542X F508del CF2 [3] I507del CF3 [16] 1677delTA C16B [17] C16D [18] [19] CFTRdele2,3(21 kb) CFTRdel2,3F [20] CFTRdel2,3R [13] Control primers for exon 3: 3i-5 3i-3 common mutations, the CF-3 kit was used, and/or restriction enzyme digestions of PCR products were performed, followed by the analysis of restriction products by agarose gel electrophoresis (Table 1); alternatively, the kits from Belgium and UK mentioned above, were used for selected samples, especially for heterozygous patients with F508del and an unknown mutation. Login to comment 51 ABCC7 p.Glu831* For confirmation of the E831X mutation, detected by SSCP analysis, the same PCR products were digested with the restriction enzyme Hpy188III, and separated by agarose gel electrophoresis. For all analyses we used the PCR primers described for the amplification of the CFTR gene [13, 22]. Login to comment 55 ABCC7 p.Arg735Lys The R735K mutation, previously undescribed, was analyzed by fluorescent sequencing (Fig. 1). Login to comment 57 ABCC7 p.Arg117His We identified one patient apparently harbouring three mutations in the CFTR gene; the genotype is F508del/F508del/ R117H. Login to comment 60 ABCC7 p.Arg117His ABCC7 p.Trp1282* ABCC7 p.Arg334Trp ABCC7 p.Asn1303Lys ABCC7 p.Gly542* ABCC7 p.Arg1162* ABCC7 p.Glu831* ABCC7 p.Glu585* ABCC7 p.Arg1070Gln ABCC7 p.Arg735Lys ABCC7 p.Arg785* From the total number of 128 patients with CF we detected both mutations in the majority of them (77), one mutation in 30 Table 2 Distribution of CFTR gene mutations in the group of 128 patients with CF Mutation Number of chromosomes Percent of chromosomes (128 patients, 256 chromosomes) Cumulative frequency F508del 144 56.3% 56.3% G542X 10 3.9% 60.2% W1282X 6 2.3% 62.5% CFTRdele2,3(21 kb) 4 1.6% 64.1% 621+1GNT 2 0.8% 64.8% N1303K 2 0.8% 65.6% 2183AANG 2 0.8% 66.4% R1070Q 2 0.8% 67.2% 457TATNG 1 0.4% 67.6% R117H 1 0.4% 68.0% R334W 1 0.4% 68.4% R735K 1 0.4% 68.8% R785X 1 0.4% 69.1% E831X 1 0.4% 69.5% 3849+10 kb(CNT) 1 0.4% 69.9% R1162X 1 0.4% 70.3% 3272-26ANG 1 0.4% 70.7% 1677delTA 1 0.4% 71.1% 1717-2ANG 1 0.4% 71.5% E585X 1 0.4% 71.9% 2789+5GNA 1 0.4% 72.3% Unknown 71 27.7% 100.0% Total 256 100.0% Fig. 1. Login to comment 61 ABCC7 p.Arg735Lys Identification of R735K mutation by fluorescent sequencing. Login to comment 64 ABCC7 p.Arg75Gln Four common polymorphisms were detected (5T allele with 4% frequency, 2694T/G, 3030G/A, and R75Q), and a specific polymorphism in three Romanian patients in exon 13 was noted, namely 2377C/T. Login to comment 66 ABCC7 p.Trp1282* ABCC7 p.Asn1303Lys ABCC7 p.Gly542* In the cohort of 142 relatives tested, we found 61 chromosomes with F508del, 6 with W1282X, 4 with G542X, and one of each with N1303K, CFTRdele2,3(21 kb), and 1717-2ANG. Login to comment 77 ABCC7 p.Gly551Asp ABCC7 p.Trp1282* ABCC7 p.Asn1303Lys ABCC7 p.Gly542* The most frequent five mutations in Europe are: F508del 66.8%; G542X 2.6%; N1303K 1.6%; G551D 1.5% and W1282X 1% [5]. Login to comment 78 ABCC7 p.Gly551Asp From the five most frequent mutations in Europe, only G551D was not noted in this study; this mutation is of Celtic origin. Login to comment 79 ABCC7 p.Glu831* With some exceptions like 457TATNG and E831X, the rest of mutations are generally common in Europe. Login to comment 83 ABCC7 p.Arg735Lys We found a new mutation, R735K, that was reported to the Cystic Fibrosis Genetic Analysis Consortium. Login to comment 84 ABCC7 p.Arg735Lys It is possible that the mutation R735K changes the activity of the ion channel through modifications of one of the consensus sites for Protein Kinase A. Login to comment 87 ABCC7 p.Arg735Lys However, until now, a second mutation has not been identified, and it is difficult to determine the pathological nature of the R735K mutation. Login to comment 92 ABCC7 p.Gly551Asp ABCC7 p.Arg117His ABCC7 p.Trp1282* ABCC7 p.Trp1282* ABCC7 p.Trp1282* ABCC7 p.Trp1282* ABCC7 p.Arg334Trp ABCC7 p.Asn1303Lys ABCC7 p.Asn1303Lys ABCC7 p.Gly542* ABCC7 p.Gly542* ABCC7 p.Gly542* ABCC7 p.Arg1162* ABCC7 p.Glu831* ABCC7 p.Glu585* ABCC7 p.Arg1070Gln ABCC7 p.Arg1070Gln ABCC7 p.Arg735Lys ABCC7 p.Arg785* Regarding the mutations detected, we noted a moderate heterogeneity with 21 mutations detected, the Table 3 Distribution of genotypes in CF patients from Romania (n=128; 256 chromosomes) Genotype Number Ethnicity F508del/F508del 46 Romanian 42 Hungarian 3 Gypsy 1 F508del/x 25 Romanian 23 Hungarian 1 Turkish-Romanian 1 F508del/G542X 8 Romanian F508del/CFTRdele2,3(21 kb) 4 Romanian 3 Hungarian 1 F508del/W1282X 3 Romanian F508del/F508del/R117H 1 Romanian F508del/R334W 1 Romanian F508del/621+1GNT 1 Romanian F508del/N1303K 1 Romanian F508del/2183AANG 1 Romanian F508del/3849+10 kb(CNT) 1 Romanian F508del/3272-26ANG 1 Romanian F508del/R1162X 1 Romanian F508del/R785X 1 Romanian F508del/1717-2ANG 1 Romanian F508del/2789+5GNA 1 Romanian G542X/G542X 1 Romanian W1282X/W1282X 1 Romanian N1303K/457TATNG 1 Romanian 621+1GNT/2183AANG 1 Romanian W1282X/x 1 Romanian R1070Q/E585X 1 Romanian R1070Q/x 1 Romanian E831X/x 1 Gypsy R735K/x 1 Romanian 1677delTA/x 1 Romanian x/x 21 Romanian 18 Hungarian 2 Gypsy 1 presence of common mutations (excepting the Celtic mutation G551D), and a similarity with the mutations detected in Italy, France and Spain [5]. 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